backup and tape rotation 1

[wfbtr]

hello-
i'm starting at a new company (very small one) and they've asked me this question:
What is your recommended backup schedule, tape rotation and method? Note: the complete XXX Network backup is approximately 30GB total.

any suggestions?
thanks.

 

[Marcs41]

one per day Mo-tue-wed-thu
one per friday, rotate every 4 weeks
one per week (the friday one) to keep in store.
one per Month (the last friday one) to keep in store.

D(ay) W(eek) M(onth)

D1 - Mo
D2 - Tu
D3 - We
D4 - Th
W1 - Fr

D5 - Mo
D6 - Tu
D7 - We
D8 - Th
W2 - Fr

D9 - Mo
D10 - Tu
D11 - We
D12 - Th
W3 - Fr

D13 - Mo
D14 - Tu
D15 - We
D16 - Th
M1 - Fr - keep

D1 - Mo
D2 - Tu
D3 - We
D4 - Th
W1 - Fr


etc, for M2-12


Marc
_{If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all. Please specify details.
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[wfbtr]

thanks marc.
what about full vs. incremental/differential?
maybe do the full friday eve., and do differential mo-thurs., since it's only 30 gigs of data?

 

[Marcs41]

If you have the time and the tapespace, do a full backup, it saves you a lot of hassle when you need to restore.

You could do incrementals Mo-Th, and always a full on Fri.
But, since it is only 30 GB, nothing stops you from doing a full one every day.

Mind you Friday means, put the tape in on friday, and the backup will run at night, way later then anyone could be in the office.

Marc
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[wfbtr]

that's what i figured.
thanks a lot for the tips.

 

[Zelandakh]

My take is slightly different but is not necessarily better:

Mon to Thurs - full backup, used/overwritten every week.
Friday's labelled weeks 1 to 12 running on a 13 week rotation. Full backup. Overwritten every 13 weeks.
Friday week 13 is brand new tape put into store.

Now you have a quarterly snapshot in the store.
You have a backup for each day for the last week.
You have a backup for each Friday for the last 3 months.

Only used 17 tapes/jobs.

<signature for rent>

 

[kmcferrin]

The most important thing about creating a backup strategy is to consider how you will be using your backup. If you are using it simply for disaster recovery purposes, then you're OK with most of the strategies listed here. If you're going to need the ability to recover a file (or database, or whatever) from the state that it was in on any given date, you're going to need a rotation that doesn't involve overwriting data. This is not that uncommon in certain highly regulated fields (finance, healthcare, law, etc).

My system is a 28 day rotation. We do full backups on Monday night, and incremental backups Tuesday-Sunday. Each full backup is done on a fresh tape that is sent to secure storage, so at the end of the year we will have 52 full tapes. Our incremental tapes are divided into Week 1 thru Week 4. After week 4 we start again with Week 1. The incremental backups are small enough that we can get roughly 6 of them on a tape. Once we have filled a set of incrementals (which are actually 4 weeks worth of tapes) they are sent off to secure storage with the full backups and we start a fresh group of incrementals.

It is fairly convoluted (and expensive), but if someone tells me "I need to see file x from June 12th of last year" I can have the tapes pulled and produce the file. If you're overwriting incremental backups as suggested above, you'll only be able to get to the week or month, not the day. That's fine for most applications (like disaster recovery), but depending on your business needs it may be a problem. So make sure that you and management are both clear on exacly what your backup system needs to accomplish, and then design a system that fulfills those needs.

 

[Marcs41]

If you're overwriting incremental backups as suggested above

No-one suggested overwriting incrementals except the daily tapes. You would have a 4 week rotation on the daily ones, a 4 week on the weekly ones (unless you want to keep these too, which give the same scheme as yours), but you should keep the Montly ones.
If then someones askes for "file x from June 12th of last year" it will be on the June tape of last year.

However, what you do have in real life is users asking for " I had a document, something about xyz, last year, but I don't know when excactly and I don't know the name"
Now THAT can be problem, but NOT an IT problem! If users ask for things with vague info like that, you will always have a fun time tracing it back!

Marc
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[wfbtr]

great points. i'll make sure to clarify my plans with the boss.
thanks again.

 

[wfbtr]

ok- i now need to make a backup plan with new information about the data. the data is ultra important for about two or three weeks, then becomes relatively useless. so the older tapes can be overwritten without any repercussion. and we won't use any offsite storage either (i may take one or two home as it's my rear on the line!)
we're using 40 gig native/80 gig compressed dlt tapes. the data we back up is about 35 gigs.
so i'm wondering what the best solution is.
thanks for any suggestions.

 

[GSG9]

excellent post KMC

however by the sound of your needs wfb something like what i have setup will work well enough..

we have 32 tapes in the rotation...at the start of the month 1 tape is taken to a safety deposite site off site so we end up with monthly backups at the end of each year..

the rest of the tapes are saved for monthly rotations (1 tape per weekday with no backups on weekends)..we are dealing with around 50GB of data so i do full overwrite with 1 week of protection (in your case 3 weeks of overwrite protection is perfect)

this way i dont have to deal with appends, the backup image is tied to a single tape and i have good overwrite protection...I also take the monday tape of every week home with me and put it in the safe...

you are going to the trouble of backing up might as well make it worthwhile, maybe its paranoia but what happens with fires? serious theft, etc...taking a tape off-site is really simple and it could save alot of heartache

first off invest in one of the DAT 72 drives and Veritas Backup exec (awesome life saver but it can cause some critical problems so beware)...but its the brand name in backup solutions...and its very powerful

if you are doing disaster recov you should also be backing up the system state somewhere as well..maybe once a week to a remote network location

 

[NetIntruder]

Depending on the backup software (and the amount of restores you expect), you may want to consider going straight to near-line w/ tape for DR purposes.

You can pick up a pair of 300GB ATA drives for about $400 and that will give you online fulls/incrementals for several months. This will allow you to be able to take your tapes off-site nightly and not have to worry about going to get them just to restore a document. Since you are the business owner and probably don't want to incur the expense of an off-site storage company, you will be the one spending the time to be a tape-jockey in restore situations (unless your tapes remain onsite, which is not a very good practice!).

My nickel's worth: Back up to near-line first at night then go to tape during the day (leaving the near-line data intact). If you have to do even a handful of restores a year, you'll still save yourself quite a bit of time.

Aside from that, Marc has the standard rotation listed perfect above.

~Intruder~

"The Less You Do, The Less Can Go Wrong"

 

[Marcs41]

an off-site storage company ... really, any local banksafe will do you know.
I even took the tapes with me at home, what are the chances of getting hit, robbed AND the server failing all at the same time?
I must add, I also had a spare HD to have a local copy first, and the backups where taken from there, so there was little downtime or overload (that was in my Exchange 5 days..)

 

[NetIntruder]

Offsite storage companies are not ideal for the new company, hence my post above
Your backup topology is perfect, i would simply add the nearline storage for quick (and cheap) recovery.

~Intruder~

"The Less You Do, The Less Can Go Wrong"

 

[technome]

Preferable I use Full backups on Sunday night, with differentials during week days, on separate tapes, tapes rotated off site to a bosses home. Sending them to an iron mine only matters in a nuclear senario, as if anything would be left.. you won't have clients, customers or employees, but you will have tapes.

With most of my clients I maintain at least a monthly tape to be archived for years. I have been involved with two incidences of litigation, involving data over 6 years old, (not present on servers).. tapes saved both clients a great deal of money; the cases involved special education student records and tax/accounting records

As far as running Full backups everyday.. great idea, but will cause an early demise of your tape unit and tapes, plus unnecessary wear on disk drive head mechanisms.

 

[wfbtr]

thanks technome.
the boss isn't worried about the cost of any new hardware, so i'll stick with the full backups.
i think my best plan at this moment is to do full with overwrites on M-Th, and a full on F- and rotate maybe 4 or 5 Friday tapes, which I'll keep at my house.
per the owner's words, any data older than a few weeks is useless.

thanks for all the input. this is a great forum.

 

[GSG9]

Another thing to consider for "special" backup situations is a DVD burner.

The new "double density" burners are just coming on the market now and pricing for under 200$ (in canada) for intenal IDE, I still don't know what the media cost for the 8.5 GB disks is but based on ram media costs (25$ CND) they wont be too cheap.

Granted it is a bit cumbersome to backup to DVD especially over a network but it is something to consider when you "close" a project. For long term restoration or simply just data access it is alot easier to handle as well.

While we are talking about backups something to consider as well is data integrity. I've read/heard so much conflicting reports/comments. Really, how reliable are tapes and how long do they last before some of the data begins to degrade and how suscetable are they to "radiation" ie being to close to electronic devices like a cell phone during transit?

and what about cds/dvds for backup...many sources say 20 years but i've seen data degrade on CDs i've burnt 4 years ago.

Also wfb...what is your server setup since redundancy on the machine is just as important as backups:

are you going with a raid array and redundant power supplies with a UPS?

 

[wfbtr]

hmm. dvd burner. that could be a secondary option.

on one dc i have the exchange server. it currently has a mirrored set. i'm going to rebuild another dc that has a 3 disk raid 5 set. basically as it is now the one dc has the exchange and all the data. i'm also trying to figure out the best way to utilize the other dc.

 

[dholbrook]

For a small company the offsite storage at a secure facility is costly. At the last two small companies I ran I invested in a fire safe (about $200) for the office, and a second which went to the boss's house. Critical tapes went to both places. You need to decide how often the critical data changes to set how often you do the backups, but the 35 GB you are dealing with will not consume a tremendous amount of time.

My recommendation is to make a Ghost CD of each critical server system for quick functional restore purposes to rebuild the operating system from a crash to operational status quickly (copy stored on site and off). Next, use a large HD on a dedicated backup system to do your nightly backups (much faster than tape for both the backup and the restore!). This then allows you to run your tape backup from these HD backups during the day with no impact on the network or your users. This greatly reduces the amount of data that needs to be backed up, as none of the applications, os, and other program files will need to be backed up, only changing data.

Set your systems up to support the backup process, not the other way around! Make your users use central server Raid 5 HD space (home directories and project space)for all valuable data storage (anything that needs to be backed up MUST be stored on the server!) so you do not have to worry about desktops systems crashing and losing critical data.

If a boss complains about how much backups cost, ask him gently how much it will cost to have everyone in the company unable to work for hours or days because critical systems crashed and have to be rebuilt manually, and all data recovered manually from paper (if possible). It puts it all into prespective quickly.

HTH

David

 

[MasterofNone]

Once you have a outlined proposal in place, you will need to gain any legal/regulatory body requirements. Certain industrys require data from 5 or even 7 years to be available (especially in the case of email). If this becomes the case, you need to make sure you leave no wholes in the backups. i.e. what happens if a email is received on monday and deleted on thursday, will your backup proceedures keep this is place for the required timescale.

Always hated looking into these sort of matters as they tend to gain momentum and what looked like a task taking a few weeks to plan, snowballs out of control.